Add shell plugin model tests

test/shell.d/base-test.sh

@@ -0,0 +1,80 @@
+#!/bin/bash
+
+if [[ ${BASH_SOURCE[0]} == "$0" ]]; then
+  echo "source test/shell.d/base-test.sh from a shell test; do not run it directly" >&2
+  exit 1
+fi
+
+ROOT=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")/../.." && pwd)
+SHELL_TEST_DIR="$ROOT/test/shell.d"
+
+export ROOT
+
+pass() {
+  printf 'ok - %s\n' "$1"
+}
+
+fail() {
+  local description="$1"
+  local detail="${2:-}"
+
+  [[ -n $detail ]] && printf '%s\n' "$detail" >&2
+  printf 'not ok - %s\n' "$description" >&2
+  exit 1
+}
+
+require_command() {
+  local command="$1"
+
+  command -v "$command" >/dev/null || fail "required command is available: $command"
+}
+
+run_node_test() {
+  require_command node
+
+  {
+    cat <<'JS_PRELUDE'
+const path = require('path')
+const root = process.env.ROOT
+
+function fail(description, detail) {
+  if (detail) console.error(detail)
+  console.error(`not ok - ${description}`)
+  process.exit(1)
+}
+
+function pass(description) {
+  console.log(`ok - ${description}`)
+}
+
+function assert(condition, description, detail) {
+  if (!condition) fail(description, detail)
+  pass(description)
+}
+
+function assertEqual(actual, expected, description) {
+  assert(
+    actual === expected,
+    description,
+    `expected: ${expected}\nactual:   ${actual}`
+  )
+}
+
+function assertDeepEqual(actual, expected, description) {
+  const actualJson = JSON.stringify(actual)
+  const expectedJson = JSON.stringify(expected)
+  assert(
+    actualJson === expectedJson,
+    description,
+    `expected: ${expectedJson}\nactual:   ${actualJson}`
+  )
+}
+
+function requireFromRoot(relativePath) {
+  return require(path.join(root, relativePath))
+}
+
+JS_PRELUDE
+    cat
+  } | node
+}